C-21A

Contractor: Learjet, Inc. Services: US Air Force Power Plant: Two Garrett TFE-731-2-2B turbofan engines Speed: 530 mph (Mach 0.81, 461 knots at 41,000 feet (12,496.8 meters) Range: 2,306 miles (3,689.6 kilometers) Ceiling: 45,000 feet (13,716 meters) Crew: Two (pilot and co-pilot); aeromedical evacuation adds medical crew of three (one flight nurse and two medical technicians). Minimal medical crew may be one flight nurse and one medical technician as required

Adopted in 1984, the C-21A is the military version of the civilian Learjet 35A business jet. It is used primarily to transport senior service officials but can be modified to transport one litter or five ambulatory patients during aeromedical evacuations.

The turbofan engines are pod-mounted on the sides of the rear fuselage. The swept-back wings have hydraulically actuated single-slotted flaps. The aircraft has a retractable tricycle landing gear, single steerable nose gear and multiple-disc hydraulic brakes.

The C-21 can carry eight passengers and 42 cubic feet (1.26 cubic meters) of cargo. The fuel capacity of the C-21 is 931 gallons (3,537.8 liters) with refueling accomplished at ground level through each wingtip tank. The safety and operational capabilities of the C-21 are increased by the autopilot, color weather radar and tactical air navigation system, as well as high frequency, very high frequency and ultra high frequency radios.

The aircraft has a crew of two and may be flown from either cockpit seat. It is equipped with an automatic navigation system to enhance crew efficiency. Four cathode ray tubes display essential information to the pilots.

Since the late 1990s, the fleet has been cut dramatically, with the Air Force scheduled to operate about 30 C-21As by the end of 2013.